RT Journal Article
T1 Selective removal of chlorinated organic compounds from soil flushing emulsions: Adsorbent regeneration with thermal-activated persulfate and surfactant recovery
A1 Sánchez Yepes, Andrés
A1 Santos López, Aurora
A1 Romero Salvador, Arturo
A1 Lorenzo Fernández, David
AB Hydrophobic organic compounds (HOCs) released into the environment can form nonaqueous phase liquids, contaminating soil and groundwater. Surfactant-enhanced aquifer remediation, followed by extracting a highly contaminated emulsion comprising surfactants and contaminants, is a promising technology for remediating polluted sites. However, the sustainable treatment of the emulsion is crucial. This study presents a two-step method for treating emulsions containing HOCs and surfactants. Firstly, pollutants are selectively adsorbed onto granular activated carbon (GAC) in a column. Secondly, spent GAC is regenerated by oxidizing adsorbed pollutants using persulfate activated at 60 ◦C. The emulsion was obtained from surfactant-enhanced aquifer remediation at a polluted site with lindane production waste, consisting of E-Mulse® 3 surfactant (12 g L− 1 ) and 28 chlorinated organic compounds (COCs) at a concentration of 9.1 gCOCs L− 1 . Selective adsorption of COCs was observed since the adsorption kinetic constant was much higher than the E3, being 31.60 and 1.76 gGAC− W⋅mg− 1 j ⋅ h− 1 respectively. The adsorption-regeneration cycle was repeated three times. It was found that the GAC adsorbed 90 mgCOCs⋅gGAC − 1 were constant after four cycles (70 % of the COCs adsorption capacity in the first step). The surfactant adsorption decreased by approximately 80 % from 108 to 26 mgE3 gGAC − 1 after the third cycle, enabling surfactant recovery from the emulsion. In addition, the remaining amount of persulfate increased from 24 to 39 %, reducing oxidant consumption. Finally, the water effluent obtained after regeneration showed reduced toxicity due to the generation of nontoxic by-products, such as short-chain acids and sulphates. The results obtained proved the GAC-based adsorption/regeneration process was effective and stable over multiple cycles.
PB Elsevier
SN 2214-7144
YR 0202
FD 0202
LK https://hdl.handle.net/20.500.14352/105136
UL https://hdl.handle.net/20.500.14352/105136
LA eng
NO References  1. Sánchez-Yepes, A.; Santos, A.; Romero, A.; Lorenzo, D. Selective removal of chlorinated organic compounds from soil flushing emulsions: Adsorbent regeneration with thermal-activated persulfate and surfactant recovery. Journal of Water Process Engineering 2024, 57, 104644 DOI:10.1016/j.jwpe.2023.104644.
NO 2023 Acuerdo transformativo financiado por la CRUE
NO Ministerio de Economía y Competitividad (España)
NO Ministerio de Ciencia e Innovación (España)
NO European Commission
DS Docta Complutense
RD 11 ago 2024